Three paradigms to deal with urban water issues are compared. The analysis focuses on their definition and objectives, the role of different stakeholders, the issues they deal with, and the possible solutions suggested. The paradigms differ in scope (from the narrow focus of the sponge city paradigm to the broad goals of eco-city paradigm) and in terms of the governance structures used to coordinate different stakeholders. The smart and sponge paradigms mainly use existing government structures. In the eco-cities approach, the citizens want to be involved through newly created governance structures. Smart and eco-city initiatives emphasize the involvement of stakeholders, while in the sponge cities approach, the initiative is often taken by the local government. Finally, in terms of expected solutions, the paradigms want to create eco- or healthy cities or improve water management to create a more healthy urban environment. After identifying the issue, alternative water-related technologies are available, like generating energy from wastewater or separating grey and brown water. Cities require different governance structures, and managing information flows in an integrated way to solve water and other issues. The experience in Europe, China, and India may help other cities choose the right paradigm.

The world is undergoing exponential urbanization, with consequences for society in general, both for cities and people, with serious economic, social and environmental implications. Therefore, it is crucial to reconsider urban models of cities, to ensure global, long-term sustainability. Numerous researchers have argued that one of these models involves eco-city projects, and this study aims to carry out a systematic review of the literature on this topic, through bibliometrics. To do so, the Smarter, Prisma and Vantage Point methods were used, reflecting the originality of the study. The results obtained show that China has aroused researchers\' interest regarding its eco-city projects, with most studies being empirical, and so this study complements them. The main contribution of this research lies in identifying the keywords most used by authors, these being eco-cities, sustainable cities (cluster 1) and eco-cities, China, sustainable urban development and eco-cycle model (cluster 2). Finally, implications for theory and practice are presented, together with suggestions for future research.